Poly epoxides

Cycloahphatic diamines react with dicarboxyUc acids or their chlorides, dianhydrides, diisocyanates and di- (or poly-)epoxides as comonomers to form high molecular weight polyamides, polyimides, polyureas, and epoxies. Polymer property dependence on diamine stmcture is greater in the linear amorphous thermoplastic polyamides and elastomeric polyureas than in the highly crosslinked thermo set epoxies (2—4). 

Phenolic Poly- ester Poly- epoxide Reinforcing Fiber... 

Poly(epoxides) are readily prepared by a ring-opening addition polymerisation catalysed by anionic, cationic or coordination catalysts. Consider the polymerisation of an epoxide bearing a single substituent ... 

Figure 1.26 Dyad configurations of a poly(epoxide). (a) Isotactic (b) syndiotactic.

An example of tacticity effects in poly(epoxides) is shown in the backbone spectrum of anionically polymerised poly(butylene oxide) in Figure 1.27 [35]. The CH resonance is narrowly split into eight peaks of essentially equal intensity, consistent with chemical shift sensitivity at the tetrad level. Evidently the CH carbon senses the tacticity of its nearest neighbours in both directions in the chain, but senses the tacticity of its next-nearest neighbour in only one direction. The CH2 carbon is split into four equal peaks, consistent with sensitivity to tacticity at the triad level. The fact that the triad and tetrad peaks are essentially equal in intensity indicates a perfectly random tacticity distribution, i.e., = 0.5. 

Borodin O, Smith GD (2007) Molecular dynamics simulations of comb-branched poly (epoxide ether)-based polymer electrolytes. Macromolecules 40 1252-1258... 

Richard C. Hartley of the University of Glasgow established Tetrahedron Lett. 2008, 49, 4771) what promises to be a powerful strategy for the convergent assembly of Spiro ketals, based on the condensation of the Ti alkyhdene derived from a thioacetal such as 19 with a lactone such as 18. James A. Marshall of the University of Virgina nicely reduced to practice J. Org. Chem. 2008, 73, 6753) the preparation and reductive cyclization of poly epoxides such as 22. Hiroki Oguri and Hideaki Oikawa of Hokkaido University demonstrated J. Am. Chem. Soc. 2008, 130, 12230) that overexpressed enzyme Lsdl9 converted 24 to lasolacid A 26. With acid, 24 cychzed to 25. 

These values of / of of poly(epoxide) chains were calculated by 0.371IM[nm.mol - /gram while those given without asterisk were calculated by 0.360/A/y. The former is due to Allen et al. (Ref. 695). The latter is based on the assumption that all valence angles of skeleton are tetrahedral. 

Poly(epichlorohydrin), see Poly(oxy(chloromethyl)ethylene) Poly(epoxides) Chromatography Benzene SEC, styragel 1263... 

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